.main-body {
    max-width: 1200px;
    margin: 0 auto;
    .left-area {
      width: 25%;
      height:100%;
      align-self: flex-start;
      min-height:800px;
      box-sizing: border-box;
      padding:10px;
    }
    .right-area{
      width: 75%;
      overflow: hidden;
      display: flex;
      flex-wrap: wrap;
    }
  }